SONARPLUGINS-2844 LCOV parsing should handle dots

Some coverage tooling (including istanbul) report with ./ prepended to the filepath

    SF:./file1.js
    DA:1,1
    end_of_record

Sonar will not able to match this path to the source file.
This patch addresses the issue by normalizing the filepath using ``org.apache.commons.io.FilenameUtils.normalize``

I have also added the corresponding tests that would fail without the patch.

Please let me know if I have missed something